A new study came out last month out of France. In it, researchers found that rats on diets consisting of 11%, 22%, and 33% Roundup-resistant genetically modified corn developed far more mammary tumors than control rats on non-GMO corn diets. GMO diet rats died earlier and in greater numbers.

Why is this study notable amidst all the other studies that seem to show the safety of GMOs?

Well, it’s one of the few long term GMO feeding studies, lasting a full two years, which, to a rat, is the equivalent of 60 of our human years. The other safety studies which found no evidence of toxicity in GM foods tend to last just 90 days, or 15 rat years. In other words, the French study studied rats over the course of an entire lifespan, whereas other studies have looked at rats for a relatively brief snippet of their lives. Cancer generally develops over a lifetime, as you probably know, so this would appear to be more relevant to human health than the shorter trials.